Physical therapy is beneficial in a wide variety of circumstances, from strength training to rehabilitating injuries. The feet and calves are often the target of therapy and exercise, due to their importance in athletic activities and frequency of injury. Not surprisingly, methods and apparatus for exercising these areas have been the subject of a high degree of inventive activity, reflected in the patent literature.
For example, U.S. Pat. No. 1,497,243 to Martin is directed to a foot exerciser intended to exert upward pressure both longitudinally of the foot and transversely, and at the same time varying the direction of pressure of the weight of the body in variously changing directions, by means of a rocking platform or pedal.
U.S. Pat. No. 2,021,801 shows a foot and leg exerciser apparatus including a pair of depressible and extendible rectangular platforms. The side edges of the platforms are secured by supports with rounded bottom edges. The supports are coextensive with the outer side edges, and have there tops flush with the upper faces of the platforms.
U.S. Pat. No. 3,297,320 to Benedetto deals with a muscle exerciser apparatus including a base or housing, a foot support platform, a U-shaped bale, a front hinge pivotally connecting bale and platform adjacent the front edge of the platform, and a rear hinge pivotally connecting the rear ends of base and platform.
U.S. Pat. No. 4,603,851 to Russell describes an exercise unit for in-place exercising includes a unitary structure having a common base member with upwardly directed pads separated by a common groove, each pad terminating in an upper foot-engaging ribbed surface surrounded by a raised ledge and generally convex sidewalls and end walls which slope downwardly from the upper ribbed surfaces into the base so as to more effectively control the resistance through compression of the pads when various exercises are performed.
U.S. Pat. No. 5,807,213 to Poncini deals with a lower body exercise apparatus including a plurality of supports, each support configured to be positioned on a horizontal surface and including a base having an inclined surface. In one embodiment, the inclined surface forms an angle between approximately 20° and 55° from horizontal. In one aspect, the plurality of supports includes two supports positioned at a distance form one another and having an angle relative to one another. The user can perform exercises on the two supports to exercise the lower body and to improve agility.
U.S. Pat. No. 5,897,464 to McLeod is directed to a method and apparatus for exercising the subtalar complex with controlled triplaner motion. The principal embodiment includes a standing platform and handrail in association with a rotatable foot plate. The foot plate is controllable and adjustable in three planes with fixed settings in all planes, including the oblique. The exerciser provides a method for isolating specific muscle groups involved with foot, ankle and calf extensions or where combinations of muscles are used, such as, with dorsiflexion-eversion or plantarflexion-inversion, while preventing tibial rotation of the foot. A second embodiment provides a more portable exercise apparatus utilizing the concepts employed with the principal embodiment wherein a rocker member is provided, attached to a support member. A foot plate attaches to the support member opposite the rocker and is pivotal in the transverse and frontal planes.
U.S. Pat. No. D298,266 to Reyneke shows a foot exerciser.
U.S. Pat. No. D347,869 to Friend pictures a stretcher for heelchords and hamstrings.